反应详情

5-Cyano-2-hydroxyacetophenone (13.57 g) was dissolved in toluene (120 ml), and pyrrolidine (6 ml) and 1,3-dimethoxy-2-propanone (15 ml) were added. The mixture was refluxed under heating for 1 hour while removing the generated water. After cooling, the reaction mixture was diluted with ethyl acetate, washed with dilute hydrochloric acid, an aqueous solution of sodium hydrogencarbonate and brine in order, and dried over anhydrous magnesium sulfate. The solvent was distilled away and the residue obtained was purified by silica gel column chromatography (ethyl acetate:hexane=2:8) to give 13.0 g of 6-cyano-3,4-dihydro-2,2-bis(methoxymethyl)-2H-1-benzopyran-4-one.

1. temperatureThe mixture was refluxed
2. temperatureunder heating for 1 hour
3. customwhile removing the generated water
4. temperatureAfter cooling
5. additionthe reaction mixture was diluted with ethyl acetate
6. washwashed with dilute hydrochloric acid
7. dry with materialan aqueous solution of sodium hydrogencarbonate and brine in order, and dried over anhydrous magnesium sulfate
8. distillationThe solvent was distilled away
9. customthe residue obtained
10. customwas purified by silica gel column chromatography (ethyl acetate:hexane=2:8)